Diurnal variation of smoke optical thickness from GOES-8

Each year more than 100 Teragrams of smoke aerosols are released into the atmosphere from biomass burning out of which 80% is in the tropical regions. These aerosols affect the radiative energy balance of the earth-atmosphere system both on regional and global scales. Satellite remote sensing plays a key role in biomass burning research by identifying sources and the spatial distribution of aerosols. In this study a new technique is explored for mapping aerosols from GOES-8 imagery.

Using hourly GOES-8 imagery, smoke aerosols are identified both over land and ocean areas during the 1998 fire episode over Central America. A Discrete ordinate radiative transfer model is used to retrieve smoke optical thickness on a pixel-by-pixel basis. The sensitivity of the results to aerosol size distribution, refractive index and surface albedo are examined. Using limited sunphotometer measurements, a comparison is made between the measured and calculated aerosol optical thickness.